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Four-Photon Interference with Asymmetric Beam Splitters

B. H. Liu·F. W. Sun·Y. X. Gong·Y. F. Huang·G. C. Guo·Z. Y. Ou
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Abstract

Two experiments of four-photon interference are performed with two pairs of photons from parametric down-conversion with the help of asymmetric beam splitters. The first experiment is a generalization of the Hong-Ou-Mandel interference effect to two pairs of photons while the second one utilizes this effect to demonstrate a four-photon de Broglie wavelength of $λ/4$ by projection measurement.

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B. H. Liu, F. W. Sun, Y. X. Gong, Y. F. Huang, G. C. Guo, Z. Y. Ou. 2007-06-25. Four-Photon Interference with Asymmetric Beam Splitters. https://doi.org/10.1364/ol.32.001320

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